What is the product of each of the following reactions?
(a) The Rosenmund reaction reduces acid chlorides to form aldehydes.
(b) DIBAL reduces esters to form aldehydes.
(c) Methyl lithium reacts with carboxylic acids to give ketones by adding a methyl group to the carbonyl carbon atom of the carboxylic acid.
(d) Reduction of nitriles by complex hydride reagents containing alkoxy groups gives aldehydes.